i mean, honestly itâs amazing the Elves had as many languages and dialects as they did, considering Galadriel (for example) is over seven thousand years old.
english would probably have changed less since Chaucerâs time, if a lot of our cultural leaders from the thirteenth century were still alive and running things.
theyâve had like. seven generations since the sun happened, max. frodoâs books are old to him, but outside any very old poetry copied down exactly, the dialect represented in them isnât likely to be older than the Second Age, wherein Aragornâs foster-father Elrond started out as a very young adult and grew into himself, and Legolasâ father was born.
so like, three to six thousand years old, maybe, which is probably a drop in the bucket of Elvish history judging by all the ethnic differentiation that had time to develop before Ungoliant came along, even if we canât really tell because there werenât years to count, before the Trees were destroyed.
plus a lot of Bilboâs materials were probably directly from Elrond, whose library dates largely from the Third Age, probably, because he didnât establish Imladris until after the Last Alliance. and Elrond isnât the type to intentionally help Bilbo learn the wrong dialect and sound sillier than can be helped, even if everyone was humoring him more than a little.
so Frodo might sound hilariously formal for conversational use (though considering how most Elves use Westron heâs probably safe there) and kind of old-fashioned, but heâs not in any danger of being incomprehensible, because elves live on such a ridiculous timescale.